BNP testing in Primary Care – repeat testing is rarely needed
NTproBNP testing as part of the Heart Failure Diagnostic and Management Pathway is going well. Although the test is relatively expensive, a level above 400pg/ml identifies those people who are more likely to have significant left ventricular systolic dysfunction (LVSD) and therefore benefit from cardiology input.
Over the past year all of those people with a level > 2000 pg/ml referred through the RSS have been offered an echo appointment within 2 weeks and almost all of those with a level 400-2000pg/ml within 6 weeks.
Overall only 1 in 8 of people with an elevated BNP are shown to have significant Left Ventricular Systolic Dysfunction but 1 in 2 of those with a BNP > 2,000pg/ml have LVSD. It is therefore important to consider other causes of breathlessness particularly in those with only mildly elevated BNP levels.
There are a large number of other factors which raise BNP, such as COPD, CKD and AF for example. The laboratory has recently made the CCG aware of an increase in the number of patients having repeat BNP assessments: with 167 in the past 6 months.
The CCG and lead cardiologist for the heart failure pathway consider that this is only appropriate if the patient is at particularly high risk for heart failure (usually with a significantly abnormal ECG) and has had a recent deterioration in their symptoms and signs. There is no recommendation that repeat BNP should be undertaken for monitoring or surveillance in primary care.
The lab will decline requests for repeat tests within 3 months unless there is detailed information on the request form documenting the deterioration and agreement for testing be sought on a case by case basis.